physical fitness attributes, vitamin d, depression, and bmd in omani's ...

European Scientific Journal October 2013 edition vol.9, No.30 ISSN: 1857 – 7881 (Print) e - ISSN 1857- 7431

PHYSICAL FITNESS ATTRIBUTES, VITAMIN D, DEPRESSION, AND BMD IN OMANI’S CHILDREN

Hashem Kilani, PhD Physical Education Department

Saif Alyaarubi, MD Child health department

Kashef Zayed, PhD Physical Education Department

Ibrahim Alzakwani, PhD Pharmacy Department

Hadia Bererhi Radiology and Molecular Department

Raghda Shukri, PhD Mental & Social Nursing

Khalid Alrasadi, MD Sultan Qaboos University, Oman

Abstract Physical fitness attributes, vitamin D, depression, and BMD in Omani’s Children 9-12 years old were investigated in 54 girls and 42 boys (average age of 12.9 ± 1.6) to assess health related fitness, body composition. Eighty two percent of the females and forty two percent of the males were deficient in vitamin D ( 0.05) in females between those with normal and those with low vitamin D levels. These results were also replicated in males except for grip and cardio-respiratory components. Initial analysis also indicates that the prevalence of symptoms of depression among Omani children was 32% ranging from mild to severe depression with negative correlation with vitamin D deficiency is significant at the 0.01 level (-0.353 2-tailed). The females are deficient in vitamin D, might be susceptible to the early diagnosis of osteoporosis and depression due to their deficiency. Children should be involved in physical activity program and meet the required sunlight exposure during all season to gain a healthy lifestyle. 156


Keywords: Physical fitness, vitamin D, depression, Omani children Introduction: Most people reach their “peak bone mass” in their 20s. This is when bones have achieved their maximum density and strength. After peak bone mass is reached, bone density remains stable during adulthood, and then begins to decline. Physicians once thought that reaching this peak depended primarily on diet, including sufficient calcium intake, and exposure to sunlight, which is necessary for the production of Vitamin D in the skin. In fact, Vitamin D is necessary for the absorption of calcium from food, for the healthy functioning of bone tissues, and thus for maintaining bone strength. A recent study has shown that in laying down the bone foundation that will serve for a lifetime, exercise is just as important as diet. This is true throughout childhood and adolescence, but especially more important around the growth spurt at puberty (Bass, Pearce, Bradney, Hendrich, et.al., 1998, Kilani, & Abu Eisheh, 2010). In this respect, number of studies showed that those boys who did the most vigorous daily activity had nine percent more bone area and 12 percent more bone strength than the less active ones (Janz, Burns, Levy, Torner, Willing, et.al., 2004). Most physically active young girls gain about 40% more bone mass than the least active girls of the same age (LehtonenVeromaa Mottonen, Heinonen, et.al., 2004). In girls, the bone tissue accumulated during the ages 11 to 13 approximately equals the amount lost during the 30 years following menopause. (Bass Pearce, Bradney, Hendrich, Delmas et.al., 1998). When astronauts first traveled beyond the Earth’s atmosphere, the first and most obvious impact was that their muscles atrophied soon after it was realized that their bones weakened (Vico, Collet, Guignandon, Lafage-Proust, Thomas, et.al (2000). Grimston, Willows, Hanely, (1993) studied gymnasts’ vs. swimmers’ bone mineral density and found that the gymnasts have more BMD than the swimmers due to high impact and gravity effect during tumbling and acrobatic skills. Egan, Reilly, Giacomoni, Redmond, Turner, (2006) searched BMD in female athletes: rugby, netball, running, and non–active as control and also found that the running group have the greatest BMD the other groups. Kemmler, Engelke,Baumann,Beeskow, Von, (2006) confirmed Egan results when they also found greater BMD in the pelvis, legs and total body bone strength for runners when compared with sedentary group. Saxon, Robling, Alam,Turner (2005) pointed out that the Mechano-sensitivity of bone is saturated over time and that pause during loading increases BMD. In a retrospective study which contained 4 impact groups, Dook, Jams, Henderson, Pice (1997) found unexpected results. The impact of activities led to an increase of bone

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mass even if calcium supplement was low (Grimston & Zernicke, 1993). Impact stimuli increase the bone quality. According to O'Connor, Lanyon, & MacFie (1982), an increase of bone mass can be explained by 61- 81% through the loading rate. This in itself explains that active young children with high agility may build and maintain their bone health faster than inactive ones especially when they play under sun lighting condition. This is of important due to the fact that athletes usually expose their skin to the sunlight more than others (Waly, Kilani, AL-Busafi, 2013). Ideally, the best place to get vitamin D is from your skin being exposed to the UV-B that is in normal sunlight. However, UV-B does not penetrate deeply into your skin especially if you have darker pigmentation. On another word the more tanned skin is, the less UV-B penetrates. Window glasses allow only 5 percent of the UV-B light range that produces D to get into your home or car. These circumstances prevail in Oman so one should consider it. Even the timing of the sun exposure is also a major factor. Sun exposure must take place when UV-B is present. The actual degree of your sun exposure is quite complex since it involves knowing the amount of UV-B and one's skin color. This doesn't sound very complex, but the amount of UV-B is not constant. It is a major variable and is influenced by a number of factors: latitude, time of year, clouds or pollution, smog and ozone smog or dust as sometimes happen in Oman, and altitude( Holick,1994). It is important to know the level of UV-B exposure. Longer exposure will not increase vitamin D production, but will increase the danger of skin damage and possible skin cancer. Severe Vitamin D deficiency softens bones. In children, the result is rickets, characterized by malformed legs. Adults may develop a rare condition called osteomalacia, distinguished by weakened muscles as well as bones. The best way to evaluate a person's vitamin D status would be to measure concentrations of an inactive form known as 25-hydroxy-vitamin D (25-D) that circulates in the blood. There are rarely obvious symptoms of Dmarginal deficiency. Vitamin D also moves calcium around our bodies, into and out of bone, muscle, hair, arteries, and cells. Both low and high levels of vitamin D appear to contribute to misbehaving calcium (Sullivan et.al. 2003). The amount of calcium (Ca) that is required to support optimal growth in children and in turn, maximize peak bone mass remains a topic of considerable debate and disagreement among scientists and clinicians alike, both within and between nations (Heaney, 2000; Specker, 2000; Holick, 2006). In addition, Ca supplementation studies in growing children have shown that an increase in Ca intake is associated with higher bone mineral status in the order of 1% to 5%, with the effect appearing to be stronger in

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the pre-pubertal years, and the greatest impact being seen in the early months of the supplementation period (Johnston, Millar, & Slemenda, 1992; Nowson Green, & Hopper, 1997). Ca supplementation in teenage girls with low dietary Ca intake (mean intake ~600 mg/day) was studied and results showed significantly greater bone mineral content/bone mineral density (BMC/BMD) following supplementation of 300 mg/day of Ca in fortified fruit juice (Lambert, Eastell, & Barker, 2000) . Stear and Coworkers (UK) showed that Ca supplementation (1000 mg/day) in a total of 131 female adolescents aged 17 years resulted in an increase in bone-size adjusted bone mass; the effect was still persistent at the femoral neck after 14 months of follow-up. Dodiuk-Gad, Rozen, Rennert, Rennert, & Ish-Shalom,(2005) examined the effectiveness of Ca supplementation on BMD 5 years after discontinuation of treatment and found that the beneficial effect of short-term (12 months) Ca supplementation on BMD in 14-year-old girls was sustained. Supplementation with milk/dairy products/milk-derived products has been shown to improve the nutritional quality of the diet to a much greater extent than that of Ca alone. In addition, increased insulin-like growth factor I (IGF1) levels have been reported in children (Bonjour, Carrié, Ferrari, Clavien, Slosman et.al., 1997). Statement of the problem and significance It is well-documented that vitamin D (in combination with PTH) plays a crucial role in the regulation of Ca and phosphorus (P) metabolism, and promotes Ca absorption from the gut and kidney tubules (Lambert, Eastell, & Barker, 2000). Supplementation trials have shown vitamin D to improve Ca absorption, lower PTH levels, and reduce wintertime bone loss in postmenopausal women (Dawson-Hughes, Harris, Palermo, CastanedaSceppa, Rasmussen, & Dallal, 2009, Dawson-Hughes, Harris, Krall, & Dallal, 2000). The child population is especially at risk for vitamin D insufficiency/deficiency. It is therefore crucial to increase bone density and bone development in children. Thus, active lifestyle and physical activity outside halls and complex buildings are necessary for children and adults. Some people in Oman live sufficiently high in the mountains for more Ultraviolet (UV) -B to reach their skins. However, many people in Oman do not expose their skin to sunlight due to the modern society they are living in, avoiding heat through shade and by means of air conditioning whether at home, work or in automobiles with shielded windows up to 50%. For both sexes, if they have to be outside for any reason, they cover both the head and body by the traditional clothing that they wear. For those reasons, the proper amount of sun is presumably not possible; and an oral form of vitamin D should be considered as supplement. High quality cod liver oil is

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probably the best choice, as it also supplies vitamin A that helps limit vitamin D toxicity and also beneficial omega-3 fats. Milk does provide vitamin D, but only about 250 units per 8 ounces. So, one would need to drink a half gallon of milk per day to receive enough vitamin D. In addition, one would need to consume 25 eggs to get the daily amount of Vitamin D which is impossible. The assumption that children in Oman are receiving the proper amount of an essential source to obtain Vitamin D from fish, milk, and eggs, must be investigated. It will be important to take calcium while receiving vitamin D, or it will tend to take calcium out of the bones. Finally, children raised in such a society who are kept safe from sun exposure spend a great deal of time indoors with video hi-tech games, computers, play stations and TV. Besides, they tend to imitate what they see from media to get the junk food and increase the sedentary life time (Kilani, Al-Hazzaa, Waly, & Musaiger, 2013, Kilani, Waly, & Yousef, 2012). A tendency to become depressed is a probability. Purpose It is imperative to assess children in Oman where sun exposure is limited and inactive lifestyles are prevalent with respect to BMD and vitamin D status. Physical assessment would also be of interest to compare and classify children according to whether they have high or low fitness levels. Muscle and bone strength in health-related physical fitness profile for an age range of between 5 and 20 years will be determined. The objectives of this research proposal are to: 1- Assess health-related physical fitness components for the sample in the study; 2- Test their vitamin D level using blood sample; 3- Determine their range body composition (BMD, FAT, LEAN MASS) status; 4- Assess their psychological status using Beck Depression Inventory (BDI, BDI-II); 5- Profile their data based on active/inactive, depress/ none depress according to Vitamin D and BMD status; Methods: The study sample (N = 97) were males and females randomly chosen immediately after their involvement in the Summer Club at Sultan Qaboos University consisting of 500 average age of 12.9 ± 1.6. Health-related fitness components were modified and measured to suit the age group such as cardiovascular endurance (Modified Bruce protocol). In the present study, children were required to perform the maximal exercise test on a motordriven treadmill. The test starts at a low work level, allowing time for warm-

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up. Children were encouraged to perform to voluntary exhaustion. The test was terminated if the subject develops signs of breathlessness, fatigue, loss of walking-coordination or when the target heart rate is achieved. Muscle strength (Dynamometer of Grip Strength), muscular endurance (Modified sit-up), and flexibility (Modified Flexibility) (Kilani, & Lala, 2001). Body composition was tested including Lumbar spine and whole body BMD, as well as body fat and lean masses were measured using DEXA Hollogic Delphi. Before the scanning, the height and weight of the children were measured. Body composition measurements were performed using a Dual Xray Absorptiometry (DXA), Hologic Delphi, W fan beam X-ray bone densitometer. The whole body was scanned and scan results were analyzed as follows: The total body scan image was divided into 10 regions including the left and right arm, ribs, thoracic spine, lumbar spine, pelvis, left and right leg, and head. The data from the 10 body regions were summed-up to provide values for the whole body mass composition; the bone mineral content (BMC) expressed in grams, bone mineral density (BMD) expressed in g/cm2, the fat content (FC) expressed in grams, the body muscle mass and body lean mass (BLM) (sum of the body muscle mass and the BMC), and Fat mass (FM). Lean mass and fat mass were also expressed as percentage of total body mass. The DiaSorin 25-Hydroxy Vitamin D assay consists of two-step procedure. The first step involves a rapid extraction of 25-OH Vitamin D and other hydroxylated metabolites in serum or plasma with acetonotrile. Following extraction, the treated sample is then assayed using equilibrium RIA procedure. The RIA method is based on an antibody with specificity to 25-OH-D. The sample, antibody and tracer are incubated for 90 minutes at 20-25°C. Phase separation is accomplished after a 20-minute incubation at 20-25°C with a second antibody precipitating complex. A NSB/Addition buffer is added after this incubation period to centrifugation to aid in reducing non-specific binding. Bound radioactivity is inversely proportional to the concentration of 25-OH-Vitamin D. A valid questionnaire was distributed to 186 randomly selected samples to identify the prevalence of depressive symptoms among them before participating in the Summer Club events. A 27 items instrument called Arabian Child Depression Inventory (ACDI) was used. ACDI is a symptom-oriented instrument for assessing depression in children between the ages 7 and 17 years (Alnufaiei & Abdullah, 2001). All participants were asked to fill in the ACDI and during June 2011, after they indicated their consent to participate in the study. It took around 10 minutes from each participant to fill the questionnaire.

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The study protocol and procedures were approved from the office of the Advisor for Academic Affairs at Sultan Qaboos University. Statistical Analysis Descriptive statistics were used to describe the data. For categorical variables, frequencies and percentages were reported. Differences between groups were analyzed using Pearson’s chi-square test (or Fisher’s exact test for cells 0.05). However, the vitamin D deficient group was associated with higher fat percent compared to those with normal vitamin D status (29% versus 24%; p = 0.011). Table 1: Association between Vitamin D and various demographic and bone densitometry characteristics (N=97) Characteristic All Vitamin D status (N=97) Normal Low p (≥50 nmol/l) (130) Normal END1 (130) High END1 (